JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 503 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 1;
   console.log(x + y); (a) 31 (b) Error (c) 4
2. 2.⚡ Which word makes a new variable? (a) put (b) make (c) give (d) let
3. 3.⚡ What does this code show?
   let name = "Riya";
   console.log("Hello, " + name + "!"); (a) Hello, name! (b) Riya (c) name (d) Hello, Riya!
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 1;
   console.log(x + y); (a) 51 (b) Error (c) 6
5. 5.⚡ Where does console.log() show its output? (a) in the console (b) in the address bar (c) on the title bar (d) on the printer
6. 6.⚡ What does this code show?
   let name = "Arjun";
   console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Arjun (d) Welcome, Arjun!
7. 7.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) console.log() (c) if (d) for
8. 8.⚡ Which JavaScript word writes in the console? (a) alert() (b) let (c) console.log() (d) if
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 3;
   console.log(x + y); (a) Error (b) 4 (c) 13
10. 10.⚡ What number does this code print?
    let a = 5;
    let b = 5;
    console.log(a * b);
11. 11.⚡ What number does this code print?
    let a = 10;
    let b = 5;
    console.log(a * b);
12. 12.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <js> (d) <code>
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 9;
    console.log(x + y); (a) 13 (b) 49 (c) Error
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 5;
    console.log(x + y); (a) Error (b) 9 (c) 45
15. 15.⚡ Which JavaScript word runs code when true? (a) let (b) console.log() (c) alert() (d) if
16. 16.⚡ Which JavaScript word repeats code? (a) for (b) let (c) alert() (d) console.log()
17. 17.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) name (b) Aman (c) Hi, name! (d) Hi, Aman!
18. 18.⚡ What number does this code print?
    let a = 28;
    let b = 16;
    console.log(a + b);
19. 19.⚡ What does alert() show? (a) a new tab (b) a table (c) a picture (d) a pop-up box
20. 20.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Aman (d) Hello, Aman!
21. 21.⚡ What number does this code print?
    let runs = 10;
    runs = runs + 18;
    runs = runs - 25;
    console.log(runs);
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 98 (b) Error (c) 17
23. 23.⚡ What number does this code print?
    let a = 27;
    let b = 8;
    console.log(a - b);
24. 24.⚡ What number does this code print?
    let a = 10;
    let b = 4;
    console.log(a * b);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 5;
    console.log(x + y); (a) 14 (b) 95 (c) Error
26. 26.⚡ What number does this code print?
    let a = 20;
    let b = 39;
    console.log(a + b);
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 1;
    console.log(x + y); (a) 3 (b) 21 (c) Error
28. 28.⚡ What number does this code print?
    let a = 2;
    let b = 3;
    console.log(a * b);
29. 29.⚡ What number does this code print?
    let runs = 15;
    runs = runs + 4;
    runs = runs - 17;
    console.log(runs);
30. 30.⚡ What number does this code print?
    let a = 9;
    let b = 25;
    console.log(a + b);
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y); (a) Error (b) 46 (c) 10
32. 32.⚡ Which JavaScript word makes a new variable? (a) alert() (b) for (c) if (d) let
33. 33.⚡ What does JavaScript add to a web page? (a) the domain name (b) actions and changes (c) only colours (d) the page title
34. 34.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) Well done, Arjun! (b) Arjun (c) Well done, name! (d) name
35. 35.⚡ What number does this code print?
    let marks = 10;
    marks = marks + 12;
    marks = marks - 5;
    console.log(marks);
36. 36.⚡ What number does this code print?
    let a = 2;
    let b = 12;
    console.log(a * b);
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 8;
    console.log(x + y); (a) 12 (b) 48 (c) Error
38. 38.⚡ What number does this code print?
    let score = 18;
    score = score + 20;
    score = score - 23;
    console.log(score);
39. 39.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, Arjun! (b) Arjun (c) Hi, name! (d) name
40. 40.⚡ What number does this code print?
    let a = 28;
    let b = 21;
    console.log(a - b);

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